Swell characteristics play an important role in determining the processability of HDPE blow molding resins. Often the intrinsic swell of chromium catalyzed resins is so high that it contributes to unacceptably high bottle weight. One option for lowering the swell of such resins is to degrade them in the presence of air along with high stresses and temperature. The disadvantage of this approach is the inability to simultaneously incorporate antioxidants (which are affected by the air) and also degrade the HDPE to reduce the swell. The use of the high temperature peroxides disclosed in this invention allows incorporation of antioxidants and at the same time degrade the polyethylene by controlled degradation of low levels of peroxides. The key concept in the invention is to use peroxides that decompose fast enough for degradation/crosslinking to be accomplished before the antioxidants are able to scavenge the free radicals generated by the peroxides. The HDPE resins modified in such a manner not only have the desired structural modifications but they also have well dispersed antioxidants which makes them suitable for blow molding applications.